Self-oscillating electric clock



July 10, 1934. c. BATTEGAY 1,965,762

SELFOSCILLATING ELECTRIC CLOCK K Filed Jan. 15, 1950 2 Sheets-Sheet 1 IN VE N TOR.

Comm/#5023 July 10, 1934. c. BATTEGAY SELF OSCILLATING ELECTRIC CLOCK 2sheets sheet 2 Filed Jan. 15, 1930 INVENTOR. j] Co/zsmoffioff yg BY 74M66 k A TOR EY.

Patented July 10, 1934 UNITED STATES SELF-OSCILLATING ELECTRIC CLOCKConstant Battegay, Levallois-Perret, France, as-

signor to Societe Anonyme des Ateliers Brille I Freres,Levallois-Perret, Seine, France, a corporation of France ApplicationJanuary 15, 1930, Serial No. 420,956 In France January 18, 1929 15.Claims.

My invention relates to improvements in clocks provided with electricself-oscillating balance means, and chiefly to clocks in which the wholeor part of the balance forms the armature of an 6 electromagnet.

The present application is closely related to my copending applicationSerial No. 284,297, filed June 11, 1928, Patent No. 1,826,719, Oct. 13,1931, and of which the present application is a continuation-in-part.

My said invention has for its object a particularly simple andeconomical construction of clocks of the said type and it ensures animproved electromagnetic efliciency for such apparatuses.

My invention chiefly consists in controlling the self-oscillatingcontact in said clocks through the movement of the balance in suchmanner that the contact will always be closed when the clock is stopped.

It further consists in various improvements and methods of manufactureconcerning such clocks, as will be hereafter specified.

In the appended drawings, given by way of example:

Figure l is an elevational view of the mechanism of an electric clock inaccordance with my invention, the balance and the contact carriedthereby being near one of the extreme positions in their paths ofmovement;

Fig. 2 is a top plan view of the mechanism of Fig. 1;

Figs. 3 and 4 are, respectively, edge and side elevational views of aring member of the escapement mechanism;

Figs. 5 and 6 are similar views of a second ring member of theescapement mechanism;

Fig. 7 is a side elevational view of a tubular member for supporting thering members of Figs. 3 to 6;

through the agency of an electromagnet; for

example, this is the case of clocks having a circular balance, in whichthe said balance wholly or partially forms the armature of an electro-Fig. 8 is a similar view of the assembled escapemagnet. However, thistype of clock offers a low electromagnetic efficiency, and for theself-oscillating contact it is necessary to use external means forgiving the first impulse to the balance. Such clocks further showcertain defects which I propose to reduce or to entirely obviate.

I In the drawings, an electric clock of the selfoscillation typecomprises a balance 1 of brass or other non-magnetic material upon whichare mounted two angularly spaced iron members 2 and 3 of U-shape. Thelatter members constitute the armature of an electro-magnet 4 andoperate by their movements toward and from the electromagnet to maintainthe oscillation of the balance 1;

The circuit of the electromagnet 4 is controlled by a movable-contact 5mounted on the shaft 6 of the balance 1 and extending parallel to theshaft 6. The contact 5 coacts with a stationary contact spring blade 7having a second spring blade 8 bearing against it to damp its naturaloscillations.

A hairspring 9, Fig. 2, returns the balance 1 toward its centralposition after the end of each oscillatory movement.

The oscillation of the balance 1 drives through its shaft 6 and a doubledriving ring 10, a gear mechanism comprising a drive wheel 11, a worm12, worm gear 13 and reduction gear mechanism 14 in the form of a trainof gears and pinions.

,The .usual mechanism for operating the minute hand of the clock isomitted as being unnecessary to an understanding of the presentinvention.

A protective high resistance 15 is connected- 7 across the terminals ofthe winding of the electromagnet 4 and comprises in part a material suchas carbon. As shown, the resistance material may be in tubular form.

The double driving ring 10 shown in detail in Figs. 3 to '7 andassembled in Fig. 8 comprises a flanged tubular member 16, upon whichare mounted two rings 17 and 18 each having a segment bent at an anglethereto to operate as a cam to actuate the teeth 19 of the drive wheel11.

The drive wheel is maintained in its successive positions by a pawl 20and a ratchet wheel 21 on the shaft 22 of the drive wheel 11.

Electrical energy for operating the clock may be supplied by a smallbattery (not shown), such as are used in flash lights. One terminal ofthe battery is connected to the outer terminal of the resistance 15which, as shown in Fig. 2, is insulated from its support and, as shownin Figs. 1 and 2, is connected to a terminal of the electromagnet 4. Theother terminal of the battery is connected to the base plate forsupporting the mechanism and which is connected to the balance shaft 6through the bearing of the latter.

The circuit when completed extends from the shaft 6 through the contact,5 thereon, the spring blade '7 and its support, which is insulated fromthe base plate, to the other terminals of the electromagnet and theresistance 15. The resistance 15 is permanently connected across thecoil controlled by the contacts 5 and '7.

In the operation of the clock, it-may be assumed that the balance isstationary. In the stationary position, the balance is displaced fromthe central position with the armature members 2 and 3 positioned atunequal distances from the electromagnet 4. This condition is caused bythe fact that the movable contact 5 is always on the one side or theother of the spring blade 7 which prevents the hairspring 9 fromreturning the armature to its exact central position.

When the circuit of the electromagnet 4 is connected to a small batteryas a source of power, the electromagnet is energized in the stationaryposition of the balance since-,the contacts 5 and 7 are engaged. One ofthe armature members is attracted by the greater force since it isclosest to the electromagnet and the balance 1 moves accordingly.Ordinarily this movement is in such direction as to separate the contact5 from the contact '7. When such separation occurs, the balance 1 andthe contact 5 are returned by the hairspring 9 to again complete thecircuit. If the inertia of thebalance is not sufficient to carry itbeyond its central position, the balance will again move in its initialdirection but with greater amplitude because of the resilience of thespring contact blade.

When the contact 5 again engages the spring contact 7 upon its returnmovement, the circuit of the electromagnet is again completed slightlybefore the balance reaches its central position. Inertia of the balancecarries it across the central position. Also, the time-constant of thecircuit which is a function of the inductance of the circuit isrelatively high whereby the maximum force of the electromagnet isdelayed after the engagement of the contacts 5 and 7 until after thebalance has passed through the central position. The balance continuesas before until the contacts are again separated to open the circuit.

In Fig. l, the balance 1 is moving in a clockwise direction near one ofits extreme positions andthe contacts 5 and '7 are about to disengage toopen the circuit of the electromagnet.

Th se oscillations continue in the manner above described, theelectromagnet operating to actuate the balance alternately in oppositedirections. The oscillations of the shaft 6 and the double ring 10thereon cause the cams of the latter to alternately engage the teeth 19and thus actuate the wheel 11 and its connected mechanism in a singledirection;

The resistance 15 affords a circuit for the discharge of energy storedin the iron of the electromagnet on the interruption of the circuit.Instead of being dissipated in the form of a spark across the contacts 5and '7, it traverses the circuit including the resistance 15 andperforms useful work in that it causes the armature to increase theamplitude of its oscillations beyond that obtaining without the use ofthe discharge circuit. The amplitude of the armatures oscillations isabout 90 or 45 from its central position.

Fig. 9 illustrates a modification of the electrothe opposite directiontoward a similar and symmetrical position.

The modified driving mechanism of Figs. 10 to 13 comprises a shaft 28adapted to be oscillated as by an armature of either of the above types.It has worm threads for rocking a segment 29 about its pivot pin 30.

The pin 30 carries an arm 31 having a cam face 32. A plate 33 secured tothe arm 31 has a cam face 34. These cam faces alternately actuate teethof an escapement wheel as the arm 31 is oscillated about the pin 30.

The characteristic features of the invention are clearly specified inthe foregoing description,

but it is understood that while the said features may be advantageouslyemployed as a whole, such features may be also employed only partiallywithout departing from the principle of my invention:

These features may be summarized as follows:

1. The electromagnet is of reduced size with reference to thebalance'and to the remainder of the clockwork whereby I obtainsmall-sized clocks or watches, particularly adapted for use onautomobile dashboards.

2. The balance carries iron armatures adapted to close the magneticcircuit of the electromagnet so as to form an electromagnet having arotary armature.

3. With a view to reduce as much as possible the magnetic connectionbetween the balance and the electro-magnet in those moments where noimpulse is required, the armatures form only a small part of thebalance, the remainder of which is made of a non-magnetic material suchas brass.

4. The iron armatures are disposed on the balance in a manner such thatthe attraction exerted by the pole-pieces of the electro-magnet issubstantially zero for the position of equilibrium 'of the balance, theattraction increasing-as soon as the balance moves away from thisposition of equilibrium in one direction or the other.

5. The contact adapted to keep up the oscillations is closed and openedby the movement of the balance in its two directions of motion, forpositions of said balance which may be symmetrical or not with referenceto its position of equilibrium.

6. The contact is disposed in a manner such that it is always closedwhen the movement stops, the stop position of the balance being verynear its position of equilibrium without coinciding therewith. Thiscondition is absolutely necessary for allowing an automatic starting ofthe balance oscillations because, as stated in paragraph 4 hereinabove,the attraction exerted by the electromagnet is substantially zero forthe position of equilibrium of the balance. This is accomplished throughthe action of the above mentioned contact comprising a yielding elementurging the hairspring away from its position of equilibrium.

. cillations of the balance with an increased action of its positiveimpulses with reference to that of its negative impulses.- Thishalf-time constant is important in particular for ensuring thepermanency of the oscillations for the case where the arcs correspondingto the impulses are symmetrical with reference to the position ofequilibrium of the balance. The keeping up of the oscillations isnevertheless still possible in this case. The current does notinstantaneously reach its normal value and consequently is smallerduring the negative impulse than during the subsequent more importantpositive impulse. This is still more true in the usual practical caseswhere the arc corresponding to the positive impulse is greater than thatcorresponding to the negative impulse.

8. A non-inductive resistance is connected with the terminals of theelectromagnet with a view to reduce the sparking at the contact and toincrease \the amplitude of the oscillations through the partial use ofthe electromagnetic energy contained in the iron of the electromagnet atthe moment of the breaking of the circuit. This resistance consists forinstance in a part of specially treated graphite.

My invention is obviously not limited to the applications disclosed asto the forms of execution described by way of example. It covers allmodifications thereof and in particular those wherein theparts areconstructed in a different manner, while serving purposes similar tothose disclosed hereinabove. As already stated the diiferent features ofthe invention need not of necessity be used all together.

What I claim is:

1. A system of clockwork mechanism with electric sustained oscillation,comprising in combination an electromagnet having a winding, anoscillatable armature constituting a balance and mounted for oscillationin the field of said electromagnet, two coacting contact memberscontrolled by the motion'of the balance and normally closed in theposition of equilibrium of said balance, and means, operable upon' theopening of said contact members, for permitting current to flow througha circuit comprising said winding whereby there is utilized in theperformance of useful work a portion of the energy stored in saidelectromagnet while the contact is closed, said means comprising aresistance without selfinduction connected to the terminals of theelectromagnet.

2. An electric clockwork comprising a balance of non-magnetic material,a stationary electromagnet, iron members carried by the'balance andforming the armature of the electromagnet, said liron members beingsubstantially equally spaced on opposite sides of said electromagnet inthe position of equilibrium of said balance whereby the resultantattraction of the balance in either direction of oscillation by theelectromagnet is substantially zero and increases as the balance passesin either direction away from this position, an electric circuit havingcontact terminals controlled directly by the balance and closed wheneverthe balance passes through its position of equilibrium and a gearworkcontrolled by the ,by the balance and forming the armature oi theelectromagnet, said balance having a position of equilibrium in whichsaid electromagnet is substantially equidistant from said iron memberswhereby the resultant attraction of the balance in either direction ofoscillation by the electromagnet is substantially zero and increases asthe balance passes in either direction away from this position, anelectric circuit adapted to be controlled directly by the balance andcomprising a movable contact secured to the balance and astationary'spring blade directed parallel to the plane of oscillation ofthe balance and a gearwork controlled by the balance.

4. An electric clockwork comprising a balance of non-magnetic material,a stationary electromagnet, spaced iron members carried by the balanceand forming the armature of the electromagnet, said balance having acentral position in which said electromagnet is equidistant from saidiron members whereby the resultant attraction of the balance in eitherdirection of oscillation by the electromagnet is substantially zero andincreases as the balance passes in either direction away from thisposition, an electric contact adapted to be controlled directly by thebalance and to be closed whenever the balance passes through its centralposition, an electrical circuit for the electromagnet, a resistanceconnecting the terminals of the winding of the electromagnet forpermitting current to flow therethrough for the performance of usefulwork when the contact is open by the balance, and a gearwork controlledby the balance.

5. An actuating mechanism for electric clocks comprising a bipolarelectromagnet, an armature therefor, comprising a disk of non-magneticmaterial and a member of magnetic material carried by said disk andhaving three spaced portions for coaction with the poles of saidelectromagnet, the spaces between the respective portions beingsubstantially equal to that between the poles of the electromagnetwhereby two of said portions may be simultaneously adjacent therespective poles of said electromagnet and contact controlled by saiddisk for controlling the circuit of said electromagnet.

6. An electric clock comprising an electromagnet, an armature thereforcomprising two spaced iron members that are magnetically separate and arotatable member for carrying said iron members within the field of saidelectromagnet, said armature having a central position in which theelectromagnet is midway between said iron members, means movable withsaid armature for controlling the circuit of said electromagnet, andgear mechanism actuated by said armature.

'1. An electric clock comprising an electromagnet, an armature thereforcomprising two magnetically separate members of magnetic material thatare mounted for rotation within the field of said electromagnet and arespaced apart by an angle of substantially 90, said armature having acentral position in which the electromagnet is midway between said ironmembers, means movable with said armature for controlling the circuit ofsaid electromagnet, and gear mechanism actuated by said armature.

8. In an electric clock, a shaft mounted to I oscillate, a balanceelement fixed on said shaft, a magnet having poles at one and the sameside of the shaft and spaced apart axially of the shaft,

arcuately spaced apart armature members movable with the shaft andadapted to be attracted by said electromagnet to actuate the balanceelement alternately in opposite directions, said armature members beingoperable through the gap between the poles of the magnet, a contactmember movable with the shaft, a relatively fixed contact member adaptedto cooperate with the contact member of the shaft, and an electriccircult including both contact members and the electromagnet.

9. In an electric clock, a shaft. mounted to oscillate, a balanceelement fixed on said shaft, a magnet having poles at one and the sameside of the shaft and spaced apart axially of the shaft, arcuatelyspaced apart armature members movable with the shaft and adapted to beattracted by said electromagnet to actuate the balance elementalternately in opposite directions, said armature members being operablethrough the gap between the poles of the magnet, said armature membersbeing of an axial dimension to substantially fill said gap whenpositioned therein, a contact member movable with the shaft, arelatively fixed contact member adapted to cooperate with the contactmember of the shaft, and an electric circuit including both contactmembers and the electromagnet.

10. In an electric clock, a shaft mounted to oscillate, a balanceelement fixed on said shaft, a magnet having poles at one and the sameside of the shaft and spaced apart axially of the shaft, arcuatelyspaced apart forked armature members movable with theshaft and adaptedto be attracted by said electromagnet to actuate the balance elementalternately in opposite directions, said armature members being operablethrough the gap between the poles, said forked armatures being ofsuificient axial dimension to position the tines of the forks in closespaced relation to the respective poles when in said gap, a contactmember movable with the shaft, a relatively fixed contact member adaptedto cooperate with the contact member of the shaft, and an electricalcircuit including both contact members and the electromagnet.

11. In an electric clock, a shaft mounted to oscillate, a balanceelement of non-magnetic ma terial fixed on the shaft, an electromagnethaving poles at one and the same side of the shaft and spaced apartaxially of the shaft, magnetic armature members mounted on thenon-magnetic balance and arcuately spaced apart thereon, said armaturemembers being adapted to be attracted by said electromagnet to actuatethe balance element alternately in opposite directions and to operatethrough the gap between the axially spaced poles of the magnet, acircuit including the magnet, and a switch included in said circuit,said switch being operable through oscillation of the balance toperiodically make and break said circuit.

12. In an electric clock, a shaft mounted to oscillate, a. balanceelement fixed on the shaft, a

magnet having poles positioned laterally of the shaft and spaced apartaxially of the shaft, arouately spaced apart armature members movablewith the shaft and adapted to be attracted by said r nately make andbreak the circuit through the magnet.

13. In an electric clock, a shaft mounted to oscillate, a balanceelement fixed on said shaft, a magnet having poles at one and the sameside of the shaft and spaced apart axially of the shaft, arcuatelyspaced apart forked armature members movable with the shaft and adaptedto be attracted by said electromagnet to actuate the balance elementinopposite directions, and the tines of which forked armature membersare adapted to cooperate with the respective poles of the magnet, acircuit including the magnet, and a switch included in said circuit,said switch being operable through oscillation of the balance toperiodically make and break the circuit.

14. An electric clockwork comprising a stationary electromagnet, abalance of non-magnetic material having spaced iron members, carriedthereby and forming the armature of said electromagnet, said balancehaving a central position in which said spaced iron members areequidistant from said electromagnet, a resilient contact member directlycontrolled by said balance and closing 1, 5 a circuit when engaged bysaid balance, said balance having a stationary position of equilibriumupon the one or the other side of said central position as determined byits engagement with said contact member, whereby, when the circuit ofsaid electromagnet is energized while the balance is stationary in aposition of equilibrium, the attraction of said electromagnet for one ofsaid iron members is greater than that for the other and said balancewill move from its stationary position.

.15. An electric clockwork comprising a stationary electromagnet, abalance of non-magnetic material having spaced iron members carriedthereby and forming the armature of said electromagnet, a spring foractuating said balance toward a central position in which saidelectromagnet is midway between said spaced iron members, means forcontrolling the circuit of said electromagnet comprising a resilientcontact member adapted to be engaged by said balance when the latter isadjacent its central position, said balance having a stationary positionof equilibrium upon the one or the other side of said central positionas determined by its engagement with said contact member, whereby, whenthe electromagnet is energized while the balance is stationary in aposition of equilibrium, the attraction of said electromagnet for one ofsaid iron members is greater than that for the other of said members andsaid balance will move from its stationary position in the direction ofthe greater attraction.

